docs: def filter(self, extractions, case_sensitive=False) -> List[Extraction]:
          """filters out the extraction if extracted value is in the blacklist"""
          filtered_extractions = []
          if not isinstance(extractions, list):
              extractions = [extractions]
  
          for extraction in extractions:
              if case_sensitive:
                  try:
                      if extraction.value.lower() not in self.black_list:
                          filtered_extractions.append(extraction)
                  except Exception as e:
                      print('Error in BlackListFilter: {} while filtering out extraction: {}'.format(e, extraction.value))
                      # most likely it s a unicode character which is messing things up, return it
                      filtered_extractions.append(extraction)
              else:
                  if extraction.value not in self.black_list:
                      filtered_extractions.append(extraction)
          return filtered_extractions